Araceae tubers such as taro, genus Colocasia, and tubers of the genus Xanthosoma, Cyrtosperma and Alocasia are widely cultivated and consumed in over 60 countries world-wide. These tubers are good sources of fine-granule starches which are potential fat replacements and/or base materials in healthy food products including baby and convalescent food and hypo-allergenic food stuffs. However, these tubers also contain "acridity" substances which can cause irritation of the skin and swelling of the mouth and throat if the tubers are not processed correctly.
Certain prior methods of removing acridity substances from Araceae tubers involve cooking processes. Cooked Araceae tubers are very sticky and viscous and have a high moisture content. Consequently, the cooked tubers are difficult to handle, dry and store, thus limiting their usefulness as a food.
Tu, U.S. Pat. No. 4,246,289, describes a method of using high amounts of alkali followed by extensive washing to remove acridity substances from Araceae tubers without cooking. Although Tu avoids the aforementioned problems of cooking tubers to remove acridity substances, the Tu method utilizes high concentrations of alkali (2 to 5%) for long periods of time (10 to 24 hours). Such high base concentrations require careful manipulations and large amounts of water for rinsing in addition to lengthy rinse times. Such lengthy rinse times can lead to starch fermentation and sanitary problems resulting from microbial growth.
It would be advantageous to have a process for removing acridity substances from Araceae tubers that avoided the problems of the prior processes. It is therefore an object of the present invention to remove acridity from Araceae tubers without cooking and, at the same time, minimizing the base concentration and time necessary to remove the acridity substances from Araceae tubers.